Purpose of RPC program numbers?

Whats the purpose of the following RPC program numbers:
100249
300598
805306368
Why the above program numbers were not listed in /etc/rpc file?
Is it dynamically assigned? These program numbers doesnt persist after rebooting the system. If any of the service is using this program number then why the service name is not getting populated in rpcinfo -s output?

server1:/# rpcinfo -s
program version(s) netid(s) service owner
100000 2,3,4 udp,tcp,ticlts,ticotsord,ticots rpcbind superuser
100099 4 ticotsord - superuser
100169 1 ticots,ticotsord,ticlts - superuser
100229 2,1 tcp metad superuser
100068 5,4,3,2 ticlts - superuser
100155 1 ticotsord smserverd superuser
300598 1 ticots,ticotsord,ticlts,tcp,udp - superuser
100249 1 ticots,ticotsord,ticlts,tcp,udp - superuser
805306368 1 ticots,ticotsord,ticlts,tcp,udp - superuser

Rgrds,
Ram.